[dpdk-dev] [PATCH 3/4] vdpa/mlx5: fix UAR allocation

[Viacheslav Ovsiienko]

This patch provides the UAR allocation workaround for the
hosts where UAR allocation with Write-Combining memory
mapping type fails.

Fixes: 8395927cdfaf ("vdpa/mlx5: prepare HW queues")
Cc: stable at dpdk.org

Signed-off-by: Viacheslav Ovsiienko <viacheslavo at nvidia.com>
Acked-by: Matan Azrad <matan at nvidia.com>
---
 drivers/vdpa/mlx5/mlx5_vdpa_event.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/vdpa/mlx5/mlx5_vdpa_event.c b/drivers/vdpa/mlx5/mlx5_vdpa_event.c
index 010543c..3aeaeb8 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa_event.c
+++ b/drivers/vdpa/mlx5/mlx5_vdpa_event.c
@@ -77,7 +77,12 @@
 		DRV_LOG(ERR, "Failed to change event channel FD.");
 		goto error;
 	}
-	priv->uar = mlx5_glue->devx_alloc_uar(priv->ctx, 0);
+	/*
+	 * This PMD always claims the write memory barrier on UAR
+	 * registers writings, it is safe to allocate UAR with any
+	 * memory mapping type.
+	 */
+	priv->uar = mlx5_devx_alloc_uar(priv->ctx, -1);
 	if (!priv->uar) {
 		rte_errno = errno;
 		DRV_LOG(ERR, "Failed to allocate UAR.");
-- 
1.8.3.1